The Note: And Then There Were Five

— -- NOTABLES

--FIORINA, CARSON JOIN INCREASINGLY-CROWDED GOP FIELD:  In an exclusive interview with ABC's GEORGE STEPHANOPOULOS on "Good Morning America" today, former Hewlett-Packard CEO Carly Fiorina said she is running for president in 2016, becoming the first female contender for the Republican nomination. "Yes, I am running for president," Fiorina said. "I think I am the best person for the job." Fiorina, 60, has never held elected office, ABC's BEN SIEGEL notes. And in an interview that aired last night with Sinclair Broadcasting's national correspondent, Jeff Barnd, retired neurosurgeon Ben Carson also made it official: "I'm announcing my candidacy for President of the United States of America." http://abcn.ws/1R5t6IK WATCH: http://abcn.ws/1GV8WhM

--WHAT COMES NEXT: Fiorina will host a live online town hall this morning. Her book, "Rising to the Challenge: My Leadership Journey," will be released tomorrow. And over the next week, she plans to make stops in the critical early primary and caucus states of Iowa, New Hampshire and South Carolina. Meanwhile, Carson will hold an announcement event in his native Detroit this morning.

--ANALYSIS -- ABC's RICK KLEIN: The Republican Party's demographic challenges are too complicated and too acute to solve on or by a debate stage. But for a party struggling with attracting a diverse, young, and female electorate, the emerging field is remarkable. The six Republican candidates expected to be in by Tuesday will include two Latinos (both in their 40s), an African-American, and a woman. More white males are on deck, of course. Still, this represents a considerable range of backgrounds, if not necessarily issue viewpoints, for a GOP that's all too aware of its short- and long-term prospects. None of this guarantees electoral success. But it does help prompt the kinds of conversations Republican leaders are seeking over the next 18 months.

--WHERE'S HILLARY THIS WEEK? Hillary Clinton will visit Rancho High School in Las Vegas tomorrow afternoon for her first visit to Nevada, and her third official campaign trip, since becoming a candidate, according to ABC's LIZ KREUTZ. According to her campaign, she will primarily discuss strengthening families and communities with a focus on immigration reform.

THE BUZZ

with ABC's VERONICA STRACQUALURSI

CHRIS CHRISTIE NOT YET IN THE CLEAR ON BRIDGEGATE, NJ LAWMAKER SAYS. New Jersey Gov. Chris Christie is not out of the woods on Bridgegate, according to John Wisniewski, Democratic chair of the New Jersey State Assembly Select Committee that has been investigating the matter. Wisniewski said that his committee's work is not done, saying it has an "entirely different agenda" than prosecutors who released federal indictments Friday against a top aide and an appointee of Christie. Wisniewski noted that prosecutors didn't explicitly exonerate Christie on Friday, saying simply that based on current evidence, no further indictments would be coming. "We need to understand who gave the order to Bridget Kelly to do this so that we could stop it from happening again," Wisniewski told ABC's GEORGE STEPHANOPOULOS yesterday on "This Week." "So, for our committee, there's an entirely different agenda than the U.S. Attorney's Office." ABC's ADAM TEICHOLZ has more. http://abcn.ws/1I8wr7i

BALTIMORE CONGRESSMAN ELIJAH CUMMINGS: "WE HAVE TO INVEST IN OUR CITIES AND OUR CHILDREN" Maryland Rep. Elijah Cummings, whose district includes parts of Baltimore, said Sunday that the unrest in his city after the death of Freddie Gray should be a lesson to city leaders around the country. "We have to invest in our cities and our children. A lot of young people feel that they have been disconnected and we have to have what I call an 'inclusion revolution,' and address issues such as joblessness and training for young people," Cummings told ABC's GEORGE STEPHANOPOULOS on "This Week." On the charges announced Friday against six Baltimore police in the death of Gray, Cummings said he agreed with the decision by the city's state attorney Marilyn Mosby, ABC' MARYALICE PARKS notes. "I feel very comfortable with regard to what Ms. Mosby has done," Cummings said. "She looked at all of the evidence and did what she had to do." http://abcn.ws/1ICFKv8

BERNIE SANDERS: "DON'T UNDERESTIMATE ME." Newly declared presidential candidate Sen. Bernie Sanders said he hopes to lead a "political revolution" for working families and against money in politics in his bid for the White House. "I think I'm the only candidate who's prepared to take on the billionaire class," Sanders, I-Vt., told ABC's GEORGE STEPHANOPOULOS on "This Week." "We need a political revolution in this country involving millions of people who are prepared to stand up and say, enough is enough, and I want to help lead that effort." Sanders has a message for his doubters, ABC's BEN SIEGEL writes. "Very few people thought that I would beat an incumbent Republican to become United States congressman from Vermont by 16 points," Sanders said. "And people weren't so sure I could beat the richest person in Vermont to become a United States senator. "Don't underestimate me," he added. http://abcn.ws/1Pg3wgt

5 STORIES YOU'LL CARE ABOUT THIS WEEK. What sounds most promising, taking the bridge to where Chris Christie is, or taking the train to where Rand Paul isn't? Dancing with Bernie Sanders, or debating with Tom Cotton? Trying to fill Michael Grimm's shoes on Staten Island, or trying to fill the silence of an empty stadium in Baltimore? Announcements are flying, roadways are open and cities are, too. ABC's RICK KLEIN looks at the five stories the ABC News political team will be tracking in the week ahead. http://abcn.ws/1DUQ3p6

NOTED: MARTIN O'MALLEY "WOULDN'T THINK OF ANNOUNCING ANYPLACE" BUT BALTIMORE. As the political discourse surrounding Baltimore has ramped up, especially among 2016 hopefuls, former Democratic governor of Maryland and potential Hillary Clinton challenger, Martin O'Malley, said yesterday that the situation in Baltimore would be central to his campaign. "We have deep problems as a country, and we need deeper understanding if we're going to give our children a better future," O'Malley said on NBC's "Meet the Press," according to ABC's KATHERINE FAULDERS. O'Malley also defended his record as Baltimore's mayor -- a job he held before becoming Maryland's governor. When asked if he would announce in Charm City that he's running for president, the Democratic presidential prospective replied: "I wouldn't think of announcing anyplace else."

WHO'S TWEETING?

@CarlyFiorina: I'm in and I'm excited to hear from you on @periscopeco at 4 pm EST this afternoon. http://apple.co/1EXjtoJ

@ZekeJMiller: .@CarlyFiorina watching @HillaryClinton in her announcement video #meta https://carlyforpresident.com/meet-carly/a>

@McCormickJohn: @ScottWalker and Absentee Governors Get Heat for Too Much Time on Presidential Trail: http://www.bloomberg.com/politics/articles/2015-05-04/scott-walker-and-absentee-governors-get-heat-for-too-much-time-on-presidential-trail

@katie_glueck: Carson on why he doesn't talk much about race: as a neurosurgeon, sees it's the brain that makes people who they are, not hair or skin color

@BrentBozell: 5 straw poll wins in SC 4 @SenTedCruz early proof true conservative can win http://thesouthcarolinaconservative.com/2015/04/28/sc-ted-cruz-sweeps-5-official-gop-straw-polls/ @ForAmerica @limbaugh @seanhannity #tcot